Speculation is rampant about what visual changes Apple may be working into the latest version of its mobile device software, iOS 7, set to be announced at Apple's Worldwide Developers Conference, June 10-14.

Sources familiar with these alleged changes in the software that powers the iPhone, iPad, and iPod Touch have said Apple is moving away from a realism look - the way elements and apps have been built to replicate real life with three-dimensional layering and faux texturing - and introducing a simpler, "flatter" design, according to Bloomberg. A report by 9to5Mac corroborates this report, citing sources that said the new elements in iOS 7 will be moving in the direction of Microsoft's Windows Phone "Metro" UI.

Image credit: Apple

The event invitation for WWDC is even being sniffed for clues. "Apple's WWDC 2013 logo, the art for the conference in which iOS 7 will be announced, has sparked speculation about flat interface design with its modern, lightweight text and other elements," 9to5Mac posted.

Daring Fireball's John Gruber, a known Apple speculator, has also commented on an "apparently rather significant system-wide UI overhaul" for the newest version of Apple's mobile OS. He posted that Apple employees have been asked to use polarizing filters on their iPhone displays, making it difficult for observers see the design changes ahead of the iOS 7 announcement.

These purported software changes are attributed to the new oversight of software design by Jony Ives, Apple's senior vice president of industrial design. Ives, head of the team responsible for the lauded iPhone and iPod hardware, has been given extended influence over mobile software design after the Apple Maps blunder and exit of former senior vice president of iOS software Scott Forstall, Bloomberg reported.

The general look and style of Apple's iOS has remained the same since being introduced in 2007. Since then, Google's Android has been visually revamped a number of times, most recently under the supervision of Palm WebOS convert Matias Duarte. New designs have also been brought to market by Microsoft with Windows Phone offerings and by Blackberry with the latest line of Blackberry 10 devices.